1. Field of the Invention
This invention relates to a power-saving control method of an image forming device, and to the image forming device. More particularly, this invention relates to a power-saving control method of an image forming device, such as a digital copier, an analog copier, a printer or an MFP, which is provided with a power saving function, and to the image forming device.
2. Description of the Related Art
In recent years, digital multi-functional peripherals (MFP) which are capable of carrying out multiple image-forming functions, including a copy function, a facsimile function, and a print function, have been widely adopted. This image forming device performs complicated data processing with the use of a high-speed CPU and a mass recording medium, etc., and it is in the tendency that various other image-forming functions are increasingly added to the image forming device.
Moreover, as a result of performing functional development which is in conformity with the user's demand for carrying many communication facilities on the image forming device and the increase of control devices for use in a color image forming device, the tendency to increase the power consumption of the image forming device further is accelerated.
For example, Japanese Laid-Open Patent Application No. 2002-094713 discloses an image forming device which is provided with a control mechanism for performing power-saving control of the image forming device, in order to reduce the power consumption and cost of the image forming device. The power-saving control performed by this image forming device is aimed at maintaining the balance between the operability at the time of power-saving mode and the efficiency of power saving or quick response at the time of returning from the power saving mode, according to the operating condition and timing of the image forming device
As mentioned above, it is in the tendency that the power consumption of the image forming device at the time of operation increases. On the other hand, the user's demand is to reduce the power consumption of the image forming device to the lowest possible level. For this reason, it is indispensable to provide an image forming device with a mechanism for reducing the power consumption of the image forming device in the standby state during which the user does not use the device, as much as possible.
The mechanism for reducing the power consumption provided in an image forming device may include a function to turn OFF the operation panel display, a control function to stop rotation of the polygon motor, a control function to lower the fixing temperature, a control function to reduce driving portions of motors of the engine unit, and a control function to suspend operation of the peripheral device, when the user's operation does not arise over a fixed time.
As for the user' operation, a timer setting for the time of shifting to the low power state in conformity with the Energy Star standard requirements, and a timer setting for the time of shifting to auto-off/sleep mode may be provided. And a user interface which enables the user to set up the power consumption function may be provided.
The depression of a power-saving shift key, the depression of a power key, and the expiration of a timer count set up by the user, etc. may be included in the shift conditions into the power saving state. The activation of a job by an application program, the depression of the power key, and a change of the device configuration in the image forming device may be included in the return conditions from the power saving state.